Power-operated tape dispenser



Patented July 27, 1954 UNITED STATES PATENT OFFICE 1 Claim.

The present invention relates generally as indicated to a power operated tape dispenser and more particularly to a pneumatically operated dispenser wherein cut-off of the tape is effected on the return stroke of the feeding mechanism.

The operation of tape dispensers such as are presently in common usage for the dispensing of moistened tape in predetermined lengths entails considerable operator fatigue since the dispensers are usually located above the work area or packing table and therefore the operator must reach up and swing the operating handle through a considerable arc in order to dispense several feet of the moistened tape as is often required in the sealing of large cardboard cartons and the like.

One object of the present invention is to eliminate the necessity of such long reaching and to enable the dispensing of predetermined lengths of moistened tape simply by operating a foot lever or the like and which upon release of the foot lever allows the tape feeding mechanism to return to its starting position to effect cut-off on the return stroke, both hands of the operator being free for the application of the tape to the carton.

Another object of this invention is to provide a control for the power operating mechanism by which the rate of feed of the tape can be regulated so as to assure proper moistening of tape as it is fed past a moistening device.

Another object of this invention is to provide means for assuring rapid return of the feeding mechanism whereby the cut-off mechanism is properly operated as an incident to such rapid return.

Other objects and advantages will become apparent as the following description proceeds.

To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawing setting forth in detail one illustrative embodiment of the invention, this being indicative, however, of but one of the various ways in which the principle of the invention may be employed.

In said annexed drawing:

Fig. 1 is a side elevation view of a typical tape dispenser with a portion of the casing broken away to illustrate the internal construction thereof for feeding and cutting the tape;

Fig. 2 is a top plan view illustrating my power control device operatively associated with the tape dispenser of Fig. 1;

Fig. 3 is a detail cross-section view taken substantially along the line 33, Fig. 2; and

Fig. 4 is a piping diagram illustrating the air flow control valves and operating mechanism.

Referring now more particularly to the drawing and first to Fig. l, the tape dispenser is shown as comprising a case I in which a roll 2 of gummed paper tape 3 is supported for rotation on suitable rollers 4:4, the tape 3 from said roll 2 passing between a feed roller 5 and a back-up, preferably spring-loaded, roller 6 and fed thereby through a slit 1 in said case I and past a moistening device 8 which may comprise a reservoir 9 for water and a brush strip H] which by capillary action draws water to the tips of the bristles for moistening the underside of the tape 3 as the latter is moved in contact therepast. Driving of feed roll 5 may be effected as through the pinion gear I l thereon in mesh with a driving gear l2, the diameters of said gears and said feed roll being selected so that approximately turning of the drive shaft I4 and thus of the gear l2 in a clockwise direction effects counter-clockwise rotation of said feed roller 5 to feed a relatively long length of tape, as for example three to four feet.

In order that the feed roll 5 will be driven only in a counter-clockwise direction as viewed in Fig. l, the shaft [4 has only a one-way driving connection with gear [2, effected as by means of a ratchet wheel I 5 non-rotatable on said shaft and a spring-loaded pawl l6 pivoted on said gear.

For the purpose of cutting the tape 3 on the return stroke of the shaft M, the latter is provided with an actuator cam or lug ll which engages one end of a knife operating lever l 8. Said lever I8 is mounted on a pivot l9 between its ends and. carries a knife 20 at its other end. Thus, as the lug I! passes the end of the operating lever I8, the knife 20 will be forced downwardly to cut the tape 3 and, of course, the movement of the lug ll past the operating lever [B will permit the knife to be restored to inoperative position by the spring 2| connected to said lever.

In the conventional hand-operated tape dispenser the manual operating handle is connected to the shaft l4 and an adjustable stop will be provided on the graduated segment 22 of the case to arrest movement of the handle to a predetermined degree so as to dispense a predetermined length of tape.

The present invention contemplates power operation of shaft [4 and in the illustrated embodiment comprises a gear 25 on said shaft I 4 with which is engaged a reciprocable gear rack 26. The end of said shaft [4 is journalled as in a bracket 21 fixed on the base 28 of the device and is provided with a lateral extension 29 to serve as a guide to maintain the gear rack 26 in engagement with the gear 25. Said bracket 21 is provided with a further extension 39 in which is threaded a stop screw SI for adjusting the stroke limit of the gear rack and thereby adjusting the 3 degree of rotation of shaft [4 so that a predetermined length of tape 3 will be dispensed during each stroke of the gear rack toward the right as viewed in Figs. 2 and 3.

The left end of said gear rack 25 is secured to the piston 35 of a signle-acting pneumatic cylinder 36 and tension spring means 31' are provided to fully and rapidly retract the gear rack 2e and piston 35 whenever air pressure in said cylinder is released or vented.

As best shown in Figs. 2 and 4, the cylinder 36 is provided with a single air inlet and air exhaust port 38 which is alternately communicated with an air pressure supply line 39 and the atmosphere through a throttling valve til, a quick exhaust valve 41, and a foot control valve 62, the latter having an inlet port 63 to which the air supply line 39 is connected.

The foot control valve 42 is operated as by a suitable lever mechanism including a pivoted foot operated lever M which through an intermediate pivoted lever 45 lifts the valve member 49 from its seat in the valve body ll to thereby permit air to flow through hose 48 to the quick exhaust valve 4|. When foot pressure on lever M is released, air pressure urges valve member :16 downwardly to seated position.

The throttling valve 49 may be, as shown, in the form of an ordinary needle valve which, upon screwing in or out of the valve member 50 there of, regulates the rate of air flow therethrough so that the tape 3 will be dispensed at just the right rate of speed for proper and complete moistening thereof as it passes the moistening brush iii.

The quick exhaust valve ll is in the form of a shuttle valve including a spring-loaded valve member i generally resembling a check valve which is unseated by air pressure in the line 48, the exhaust port 52 then being closed by said member 5| whereby air under pressure is allowed to flow through said valve 4i and through valve 40 into the pneumatic cylinder 35. When the air pressure in line 49 is cut off by closing of valve 42, the valve member 55 will be actuated by the spring 53 to close the intake port as and to open the exhaust port 52 whereby the air from the pneumatic cylinder 39 may be exhausted through the throttle valve 50 and through the quick exhaust valve 4! to the atmosphere.

In operation, the tape dispenser is mounted at a convenient place on or above the packing table and the operator turns the adjusting screw 3i so that the desired length of tape 3 will be dispensed during each forward stroke of the piston 35 and gear rack 26, and for this purpose the extension 30 may be provided with indicia, as shown, with which the end of the screw 3i is adapted to be aligned. When it is desired to dispense such predetermined length of tape 3, the operator simply depresses the foot lever M to open the foot control valve 62 and thereby allow air under pressure to flow from supply line 3d and through the foot control valve, the line as, the quick exhaust valve 41, and the throttle valve 19 into cylinder 36, the valve 42} of course being adjusted so that the piston 35 in said cylinder 35 will be actuated against the force of spring 31 and that required to rotate the feeding mechanism at a desired rate of speed for proper moistening of the tape. Then, upon re lease of the foot lever the air pressure in the air supply line 39 will immediately effect movement of the valve member 2-5 to a closed position and the consequent drop or equalization of pressure in the line 48 between the foot control valve 42 and the quick exhaust valve ll will permit the spring 53 in the latter to move the valve member 5! to close the intake port 54 and to open the exhaust port 52 whereby the air in cylinder 36 will be exhausted to the atmosphere through the throttle valve ll! and the quick exhaust valve 4|. It is to be noted that the upper mushroom portion of the valve member 55 seats in the body l! while the lower stem portion is merely slide-guided in said body 41 without packing rings or the like whereby the consequent drop or equalization of pressure is made possible through leakage occurring between the stem portion of the valve member and the bore in the body ll in which said valve. member stem is slidable. Since the spring 3'! is now effective to retract the piston 35 and the gear rack 26, the air will be rapidly exhausted without excessive build-up in pressure between the piston 35 and the throttle valve 40 whereby the piston movement is substantially unimpeded and relatively rap-id. In this way, the lug il of the cut-off mechanism rapidly trips the knife 20 to effect a clean cut of the tape 3. The lug l! in passing the knife operating mechanism permit restoration thereof to inoperative position so that as soon as the foot lever 4 is again depressed, the operation of the feeding mechanism can proceed with the tape 3 being forced through the case i and past the moistening brush it].

Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in the following claim, or the equivalent of such, be employed.

I therefore particularly point out and distinctly claim as my invention:

The combination with a tape dispenser of the type which includes an operating member which, when moved a predetermined distance in one direction at predetermined speed, feeds a predetermined length of tape at predetermined speed past a tape moistening device and which, when moved in the opposite direction, operates a knife to sever the length of moistened tape; of a power device for operating said member, said power device comprising a fluid motor including a movable element operatively connected to said operating member, a

fluid pressure supply line leading to said motor for effecting fluid pressure actuation of said movable element in one direction, valve means in said line effecting alternate supply and release of fluid under pressure to and from said motor and including an adjustable needle valve for effecting control of the rate of flow of fluid under pressure to said motor to regulate the rate of movement of said movable element and thus to regulate the rate of movement of said operating member in such one direction for proper moistening of the tape, and spring means for actuating said movable element and operating member in th opposite direction upon release of the fluid under pressure as aforesaid for operation of the knife.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 897,509 Anable Sept. 1, 1908 922,530 Shoemaker May 25, 1909 1,250,790 Brownson Dec. 18, 1917 1,271,603 Mortimer July 9, 1918 1,455,859 Brooks May 22, 1923 1,726,102 Forman Aug. 27, 1929 2,022,521 Pierce Nov. 26, 1935 2,083,219 Clements et a1 June 8, 1937 2,252,418 Shelley Aug. 12, 1941 

